CAKIR, Z.; SENDUR, A. A note on epidemiologic models: SIR modeling of the COVID-19 with variable coefficients. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 105, n. 1, p. 43–51, 2022. DOI: 10.31489/2022m1/43-51. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/464. Acesso em: 3 jul. 2025.